The apparatus of this invention is designed to support, position and cushion the patient during spinal surgery.
Present standard operating procedure for spinal operations calls for placing the patient face-down in a horizontal position on a flat surgical table top. In this position, the patient's greatest weight is supported primarily by the abdomen on the flat table top. Further, the knees are straight and the legs extended.
This creates two problems with which the spinal surgeon must contend and which have an adverse, complicating effect upon the surgical procedure, thereby injecting unnecessary variables. First, of key importance in any operation is the control and minimization of blood loss. Not only does excessive loss of blood during an operation pose an immediate risk of harm to the patient, due either to the loss of blood itself or the risk of hepatitis infection concommitant with any blood transfusion, but excessive bleeding at the operation site also obscures the operatory field hindering the ability of the surgeon to see his work area clearly.
Blood loss during a spinal surgical operation is a function of the degree of intraspinal venous engorgement; that is, whether the blood vessels in the spinal area are full and under pressure, or drained. If the patient is positioned face down on the operating table (as in the standard operating procedure) the abdominal area supports a large portion of the patient's weight. This in turn causes the viscera to be forced against the spinal column. This causes intraspinal engorgement as the blood in the spinal area is retained there and the blood in the visceral area is forced into the spinal area. This situation is exacerberated for the obese patient with a a pendulent abdomen.
Second, when the patient is lying face down on the surgical table with his knees straight and his legs extended, the spinal column is under a compressive load. For any operation on the spine, the surgeon would prefer to have the spine in a flexed position; that is, in a relaxed state under no load. One previous attempt has been made to achieve this result. This entailed placing the patient on his knees in an upright fetal position wherein the patient's knees were pulled forward to his chest. This did flex the spine, but the patient was placed into a very uncomfortable position wherein free breathing was restricted. Also, the viscera was forced against the spinal column so that blood loss was accelerated.